A spherical object with a temperature of 700 oC, made of carbon steel with a diameter of 3 cm, will be cooled to 370 oC by an air flow with a temperature of 35 oC and a heat convection coefficient of 90 W/m2K. Calculate the time (s) required to cool the body, ignoring the temperature gradient inside the body and making any other assumptions you deem necessary. The heat transmission coefficient of carbon steel can be 45 W/mK, its density is 7800 kg/m3 and its specific heat is 480 J/kgK.

A spherical object with a temperature of 700 oC, made of carbon steel with a diameter of 3 cm, will be cooled to 370 oC by an air flow with a temperature of 35 oC and a heat convection coefficient of 90 W/m2K. Calculate the time (s) required to cool the body, ignoring the temperature gradient inside the body and making any other assumptions you deem necessary. The heat transmission coefficient of carbon steel can be 45 W/mK, its density is 7800 kg/m3 and its specific heat is 480 J/kgK.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.19P: 1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the...

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